1. Field of the Invention
The present invention relates to a transflective color filter substrate on which a plurality of color filters, such as red (R), green (G), and blue (B) color filters, are formed, a method of manufacturing the color filter substrate, and a method of manufacturing an electro-optical device. In addition, the present invention relates to an electro-optical device and an electronic apparatus employing the color filter substrate.
2. Related Art
A reflective liquid crystal display device has advantages in that the power consumption thereof is small because it does not use a light source, such as a back light, and in that the portability thereof is excellent because the reflective liquid crystal display device can be made very thin. For these reasons, the reflective liquid crystal display device has been widely used in display units of various portable electronic apparatuses. However, since the reflective liquid crystal display device displays images using an external light source, such as natural light or an illuminator, there is a disadvantage in that the visibility of the display deteriorates in a dark place.
Therefore, a liquid crystal display device has been suggested, in which the visibility has been improved by using an external light source in a bright place similarly to a conventional reflective liquid crystal display device and by using a light source, such as a back light attached to the display device, in a dark place. That is, since this liquid crystal display device employs a display method combining the reflective display mode and the transmissive display mode, it can switch the display mode into either the reflective display mode or the transmissive display mode depending upon the circumstantial brightness. Using this transflective liquid crystal display device combining the reflective display mode and the transmissive display mode, it is possible to decrease the power consumption and to display a high quality image even when it is dark.
Recently, as portable electronic apparatuses are widely popularized, it is desirable to colorize a liquid crystal display device. Furthermore, it is also desirable to colorize an electronic apparatus, which is provided with the aforementioned transflective liquid crystal display device. A transflective liquid crystal display device provided with a color filter substrate is used as the transflective color liquid crystal display device to meet the requirements.
In the transflective display mode of the transflective color liquid crystal display device, the incident light from the external light source into the liquid crystal display device passes through a color filter, and is reflected from a reflective film provided below the color filter. Then, the reflected light passes through the color filter again, and then reaches an observer. In brief, the external light passes through the color filter two times. Furthermore, in the transmissive display mode, the light emitted from a light source, such as a back light, passes through the color filter one time, and then reaches the observer. For this reason, when the same color filter substrate is commonly used in both the transmissive display mode and the reflective display mode, there is a disadvantage in that the chroma or brightness of the displayed image in each display mode is insufficient.
That is, when a color filter having low pigment density is used to obtain an optimum chroma in the reflective display mode, the chroma of the displayed image is apt to be insufficient in the transmissive display mode. On the other hand, when a color filter having high pigment density is used to obtain an optimum chroma in the transmissive display mode, the brightness of the displayed image is apt to be insufficient in the reflective display mode.
For this reason, a transflective liquid crystal display device capable of compensating for the lack of the brightness in the reflective display mode has been suggested, wherein the density of the color filter substrate in the transflective liquid crystal display device is set so as to obtain an optimum chroma in the transmissive display mode, and the color filter substrate has regions in which the color filters are not provided in a reflective display region, that is, regions (hereinafter, referred to as “uncolored reflection regions”) in which a reflective film is not covered with the color filters. In this transflective liquid crystal display device, a reflective film is formed on one of a pair of glass substrates that constitute a liquid crystal panel, and color filters are formed on the reflective film using the photolithography method. However, in the uncolored reflection region formed by the photolithography method, the color filters have concave portions, and thus there is a disadvantage in that the flatness of the color filters is compromised.
The present invention is provided to solve the above disadvantages, and it is an object of the present invention to provide a color filter substrate, an electro-optical device, and an electronic apparatus capable of improving the brightness of the reflective display and the chroma of the transmissive display using an inkjet method and of reducing manufacturing cost, and to provide a method of manufacturing the color filter substrate and a method of manufacturing an electro-optical device.